Hitachi ShadowImage for IBM z/OS User"s Guide (T5213-96002, June 2007)

Preparing for ShadowImage™ for IBM
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z/OS
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Hitachi ShadowImage™ for IBM
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z/OS
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User’s Guide
• Logical DKC (LDKC), CU, LDEV number
You can use volumes whose LDKC:CU:LDEV (a combination of an LDKC
number, a CU number, and an LDEV number) is within the range of
00:00:00 to 00:FE:FF, or 01:00:00 to 01:FE:FF.
• Number of T-VOLs per one S-VOL
You can assign up to three T-VOLs to one S-VOL. However, you cannot
assign two or more S-VOLs to one T-VOL.
• Maximum number of pairs
Up to 16,384 SIz pairs can be created (when S-VOLs and T-VOLs are in a
one-to-one relationship).
Even if the above requirements are fulfilled, the URz journal volumes cannot
be used for creating SIz pair.
ShadowImage for z/OS Software Requirements
To use ShadowImage for z/OS, all USP V hardware, microcode, and software
required for SIz operations must be installed and enabled. You also need to
purchase the license key of ShadowImage for z/OS and install it in Storage
Navigator. For detailed information about the license key and software
installation, see the Storage Navigator User’s Guide.
Note that you must operate the Storage Navigator computer in modify mode
to perform SIz operations. Users in view mode can only view SIz information,
but they cannot create new pairs or change the pair status. For information
about how to set up and use the Storage Navigator computer, see the Storage
Navigator User’s Guide.
License Requirements
SIz license capacity will be required for SIz S-VOLs, T-VOLs, and reserved
volumes. You need to make sure that the SIz license capacity will be larger
than the total capacity of these volumes when you decide the SIz license
capacity.
Even if a volume is used for multiple purposes, only the capacity of this
volume itself is added to the total volume capacity. There is no need to
multiply the capacity of this volume by the number of purposes it is used for.
For example, if you specify a volume as an S-VOL, and use it as a reserved
volume as well by setting its reserve attribute, only the capacity of the volume
itself is added to the total volume capacity and there is no need for it to be
doubled.
The following illustrations are case examples showing how to calculate the
total capacity of volumes that you will use with ShadowImage for z/OS. For
these examples, the capacity of each volume is assumed to be 1. The colored
volume or volumes represent the volumes that are used.